The doors of many appliances such as refrigerators, ranges, microwave ovens, etc. typically have a flexible, tubular gasket around their perimeter for sealing and a variety of other reasons. Previously, such doors have been fabricated by joining together front and back pieces. This has enabled the door manufacturers to use gasket assemblies which include a pair of joined, parallel, elongated cylindrical members. One member was then either pushed through a slot or slots provided on the "back" piece of the door or wound around the perimeter of such a back piece which was then fitted into a receiving cavity in the "front" piece of the door. An exposed cylindrical member formed the gasket while a remaining cylindrical member, hidden within the door, held the gasket cylindrical member in place against the door.
The cylindrical members of these gasket assemblies often were formed from a single knitted, metal wire tubular core covered with braided, glass fiber jackets.
There has been a desire on the part of appliance manufacturers to develop a one-piece door construction in such appliances to reduce fabrication costs. Gaskets would have to be attached to such doors from an exterior side using some type of mechanical fastening.
One approach for mechanically mounting such gaskets to one-piece doors has been disclosed in U.S. Pat. No. 4,822,060 to Moyer et al. That patent discloses providing a flexible, hollow cylindrical gasket with clip-type fasteners protruding along one side thereof. Such gaskets are formed from a hollow, tubular, knitted wire core and braided, glass fiber outer jacket, somewhat similar to the cylindrical members of the old gasket assemblies. A single wire member is bent at several locations along its length to form a series of connected clip members.
Various methods of automatic manufacture are proposed in that patent for inserting the bent wire member into the core, namely while the core is being knit or when it exits from the knitter and before the core and bent wire member are passed through a braider. It is believed that these methods of assembly are not practical. From an examination of a commercial product believed to be made and sold under the above-identified patent, it appears that the bent wire member, which forms the plurality of interconnected clip members, is inserted into the hollow center of the tubular wire core after the outer jacket is braided onto the core. It is further believed that the bent portions of the wire are pressed through the wire core and the surrounding fabric jacket by hand.
There are several limitations to the gaskets of U.S. Pat. No. 4,822,060 as represented by the commercial product. First, they require considerable hand labor to assemble. Second, the wire forming the clip members has to be passed through the inner core and outer jacket without damage to either. As a result, the wire used must be fairly thin and the clip portions tend to be easily deformed or damaged. Third, because the wire must be inserted into the gasket after the continuous outer jacket has been braided over the continuous core, assembly becomes more cumbersome and difficult as continuous gasket length is increased to more than a few feet. The fabrication of significant continuous lengths of undamaged, unflawed gasket with the wastage which would be involved would be prohibitively expensive.
In addition to the foregoing limitations, thin wire is used in the commercial product apparently to enable the clip portions to be pressed through such gaskets. This wire does not provide a significant spring force for firmly attaching the gasket to the door or other mounting member. The thin wire provided in the commercial product is extremely flexible and does not trap any significant area of the gasket between itself and the door or other mounting member. It therefore does little to prevent the gasket from rolling to either side of the attachment points or bending between the attachment points.
U.S. Pat. No. 4,822,060 suggests in FIG. 4 the positioning of the thin, bent wire member between the tubular wire core and the outer jacket. The thin, bent wire member is identical to the wire member disclosed in the initial embodiment in FIGS. 1-3 of that patent. However, no method of fabrication of the embodiment of FIG. 4 is disclosed or suggested.
The hand-assembly method apparently employed for making the commercial product, in which the bent wire member is inserted after the core and outer jacket are woven, cannot be employed to make the suggested gasket configuration of FIG. 4 as there is no disclosed method for inserting the bent wire member between the two tubular members after the outer jacket is braided onto the knitted tubular core. The other methods proposed in U.S. Pat. No. 4,822,060 for automatic gasket assembly essentially require the clip members to be directly connected to one another for feeding through a knitting (or braiding) machine.
It would be beneficial to provide flexible gaskets with protruding fasteners for mounting to appliance doors and other members which can be attached to the doors or other members a firmly as desired.
It further would be beneficial to provide flexible gaskets with protruding fasteners in which the gaskets do not tend to roll around such fasteners.
It further would be beneficial to provide hollow, tubular gaskets with the aforesaid characteristics for light weight and durability.
It further would be beneficial to provide gaskets and other gasket-like devices with the foregoing characteristics in a form which further includes a plastic and/or rubber outer covering along at least some portion of the device.
It further would be beneficial to provide continuous, elongated gaskets, and gasket-like devices such as molding, etc., with embedded, protruding fasteners which exhibit superior mounting stability.